When the script for "Superman Returns" called for a scene with the late Marlon Brando, the production team turned to the visual effects masters at Rhythm and Hues to bring the actor "back from the dead."
Using footage shot for the 1978 Richard Donner classic "Superman: The Movie," visual effects supervisor Derek Spears and his team were charged with reworking the footage so it would match the style, lighting and camera angles of Bryan Singer's 2006 update.
"We used footage that may or may not have appeared in the Donner film," Spears said, "but it was all shot for the original movie."
Although the process was complicated and involved around 30 people working for months to bring Brando's portrayal of Superman's father, Jor-El, to a whole new audience of moviegoers, the concept is not new.
In 1993, on day 52 of a 60-day shoot, Brandon Lee, son of the great martial arts master and actor Bruce Lee, was killed during filming of the dark comic book adaptation of "The Crow."
With the support of Lee's family, it was decided that the film would be finished and released, but director Alex Proyas had a dilemma.
There were still scenes to be shot that featured Lee's character.
Using a stunt double, some footage that had already been shot and some seamless visual effects, the filmmakers were able to finish the movie and the audience was none the wiser.
But even before there were digital effects to mask missing performers, filmmakers have had to find solutions to similar problems.
When Bela Lugosi died during the shooting of Ed Wood's "Plan 9 From Outer Space" -- a film considered by many to be the worst ever made -- the director famously had his wife's chiropractor play the veteran actor's role, with a cape drawn across his face to mask the casting change.
Spears says that if you don't notice the work he and his team did on "Superman Returns," then they've done their job well.
"That's ultimately the goal," he said, "to make it look seamless."
To that end, the process of Brando's reanimation required many steps to ensure that the audience wouldn't notice the difference between the new footage and the old.
The whole procedure was catalogued and explained in a short video you can watch by clicking here.